Bitcoin vs BTCUSD

What do we look at many assets beyond Bitcoin? Simple to not lose context of what we are really doing when we are trading one asset for another. To be long BTC/USD is different than just owning bitcoin. When we say we are long BTC/USD we are really saying 2 things. We defining an exchange rate for one asset in terms of another. I could express this just as easily by quoting the relation ship USD/BTC it is still the same pair. As simple as this all seems its actually quite an overlooked distinction in trading when you here folks say that you own BTC or that you are long in a specific pair. Below a simple illustration to reflect what we are talking about: